/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.io.gcp.spanner;



import com.google.cloud.spanner.KeySet;

import com.google.cloud.spanner.Mutation;

import com.google.cloud.spanner.Mutation.Op;

import com.bff.gaia.unified.vendor.guava.com.google.common.collect.Iterables;



final class MutationCellCounter {

  // Prevent construction.

  private MutationCellCounter() {}



  /** Count the number of cells modified by {@link MutationGroup}. */

  public static long countOf(SpannerSchema spannerSchema, MutationGroup mutationGroup) {

    long mutatedCells = 0L;

    for (Mutation mutation : mutationGroup) {

      if (mutation.getOperation() == Op.DELETE) {

        // For single key deletes sum up all the columns in the schema.

        // There is no clear way to estimate range deletes, so they are ignored.

        if (MutationUtils.isPointDelete(mutation)) {

          final KeySet keySet = mutation.getKeySet();



          final long rows = Iterables.size(keySet.getKeys());

          mutatedCells += rows * spannerSchema.getCellsMutatedPerRow(mutation.getTable());

        }

      } else {

        // sum the cells of the columns included in the mutation

        for (String column : mutation.getColumns()) {

          mutatedCells += spannerSchema.getCellsMutatedPerColumn(mutation.getTable(), column);

        }

      }

    }



    return mutatedCells;

  }

}